Machines such as a wheel loaders, wheeled scrapers, track-type tractors, on and off-highway haul trucks, motor graders, and other heavy equipment generally include hydraulic systems that facilitate different operations of the machines, including steering, braking, and tool movement, among others. These hydraulic systems include an assembly of components that work together to deliver pressurized hydraulic fluid to drive the operations of the machines. Typically, the components include a fluid tank dedicated to holding and filtering a desired supply of hydraulic fluid and an associated breather to protect the hydraulic system from contamination found in harsh industrial environments.
The breather is usually attached to a top of the fluid tank. The breather contains a filter element and functions by inhaling and exhaling air to regulate pressure within the fluid tank. The filter element of the breather cleanses the air entering the fluid tank. When the breather inhales, it serves as a pathway for air to enter the fluid tank without also transmitting accompanying pollutants found in the environment into the fluid tank. When the breather exhales, it discharges air and filtered particles dislodged from the filter element of the breather into the environment, while maintaining the fluid tank at a desired pressure.
During operation of the machine, hydraulic fluid housed in the fluid tank can churn and splash onto the filter element of the breather and/or deposit a mist on the filter element of the breather. This can accelerate wear of the breather and reduce its durability. Hydraulic fluid entrained in the air can also be discharged into the environment, if not properly filtered. The entrained hydraulic fluid can coat the surface and internal pathways of the breather, as well as the surrounding surface of the fluid tank. This coating can attract dust, dirt, and other pollutants, which can accumulate in the internal pathways of the breather and block the passage of air into and out of the fluid tank. This can undermine the breather's ability to maintain the fluid tank at a desired pressure, which can result in structural damage to the fluid tank. Additionally, the discharge of hydraulic fluid into the environment can present environmental concerns. The accumulation of dust, dirt, and other pollutants on the breather and the surface of the fluid tank can also result in an aesthetically displeasing appearance.
An exemplary breather is described in U.S. Pat. No. 1,841,691 that issued to Wilson (“the '691 patent”) on Jan. 19, 1932. The breather is located above a top surface of a tank, and a stamped metal disk having a small central opening is positioned between the breather and the tank. A pan positioned above the stamped metal disk further separates the breather from the tank and collects solid or liquid particles filtered by the breather. To exit the tank through the breather, air laden with undesirable vapors must pass through the small central opening, a row of apertures along vertical walls of a washer, and a receptacle with a perforated bottom to reach an absorbent material. The absorbent material absorbs the undesirable vapor, entrains the air with moisture, and discharges the moisturized air into the environment. A reverse route is similarly followed for air entering the tank.
Although adequate for some applications, the configuration disclosed in the '691 patent may be less than optimal. This is because the central opening may be too small to properly maintain atmospheric pressure in the tank. In addition, the apertures of the '691 patent are vertically offset from the absorbent material, which may reduce the ability of the absorbent material to capture entrained liquids. Also, entrained liquids filtered by the breather may not be provided with an adequate return route back to the tank. This may require ongoing maintenance and service, which can be time consuming and expensive.
The breather assembly and mounting configuration of the present disclosure solves one or more of the problems set forth above and/or other problems in the art.